The present invention relates, generally, to improved vegetation trimmer and edging units for lawn and garden use; and, more specifically, to a combination vegetation trimmer and edging unit, further providing, in a preferred embodiment, a multi-position handle, a roller edging guide with a flange concentrically located about the motor shaft, dual-position activation switches symmetrically located about the central shaft of the unit; and, a power source located symmetrically in-line with the center of the shaft of the unit.
For many years, powered line or blade-type trimmers have been offered for the trimming of lawns, cutting in the horizontal plane. Similarly, powered edgers have been offered for the edging of lawns adjacent to walkways and driveways, cutting in the vertical plane.
Consumers, in their desire to purchase and utilize only one tool for these similar lawn cutting purposes, have attempted to use trimmers of the aforementioned type, intended for use in a horizontal position for grass trimming purposes, in a rotated, vertical plane to function as a lawn edger.
Most of these units have a control handle, containing the activation switches, and an additional front handle for support of the unit""s weight and for use in maneuvering the unit in use. Disadvantageously, however, due to the designs of these handles, many units are not convenient or safe to use for edging. Often only a single front handle position is provided, optimized for use in the lawn trimming horizontal plane. Accordingly, when the unit is held in the edging position, the front handle is generally in an inconvenient and off-balance position. This condition is aggravated by the non-symmetrical positioning of the heavy power source in many units. With such units, a position of balance for trimming will not be a position of balance for edging.
Further contributing to the inconvenience in use of such units in the vertical plane edging position, the activation trigger is frequently located in a position suited only to trimming in the horizontal plane. A switch or trigger that is not in a convenient position raises the dual concerns that the unit might be started by accident, resulting in a unit that is both difficult to use and unsafe, or might be difficult to stop in an emergency situation.
Recent units have been developed that make it more convenient and comfortable for the operator of the unit to more easily hold the unit in the desired vertical edging position. Some such units have devices provided for the rotation of the trimmer head about its shaft, in effect allowing rotation of the cutting plane. Often, however, such rotation devices are cumbersome and inconvenient to use.
For edging use, orientation devices also have been developed to help guide the trimmer with a consistent motion, so as to give the trimmed edge a neat appearance. Many such devices of this type comprise wheel-and-bracket arrangements, rubbing pads, or wire guide loops, configured to hold the trimmer at a relatively consistent position.
Most of the wheel-and-bracket arrangements are of an A-frame type, with wheels mounted on the frame and the frame clamped to the shaft of the trimmer. Some of these types of devices allow the user to loosen the clamp and rotate the trimmer into an edger position. U.S. Pat. No. 4,922,694 to Emoto and U.S. Pat. No. 5, 450,715 to Murray are examples of this kind of device. Some of these devices, such as U.S. Pat. No. 4,224,784 to Hansen et al. have the wheels rotated 90 degrees to function as an edging guide. Still other designs have plates clamped to the shaft which held wheels in an edging configuration, such as in U.S. Pat. No. 4,981,012 to Claborn. Other devices, such as U.S. Pat. No. 5,228,276 to Miller, are merely axles which bolt to the trimmer.
Through the use of these wheel-and-bracket attachments, the orientation of the cutting plane to the adjacent vertical curbing surface can be controlled in a more consistent manner. Those devices lacking the further enhancement of a vertical-plane feature are less effective, and many of the wheels are so small in diameter that they cannot accommodate imperfections in the reference surface without bounding. In general, these devices can be unwieldy to install, to use, and to store.
These wheel-and-bracket devices are usually low-friction in use, however, making them superior to the high-friction wire loop and rubbing block orientation devices. Such high-friction devices will grab and skip over the reference surface when used, leading to inconsistent results. Additionally, the rubbing block or wire loop features share another disadvantage with the wheel-and-bracket attachments: the edging position, as effected by the orientation device, is dependent upon the operating angle of the trimmer unit. The user must maintain a consistent operational position at all times to avoid a varied edging effect. Line trimmers with these orientation devices, therefore, do not provide a single tool solution to the problem identified by many consumers.
It is, therefore, readily apparent that there is a need for a new and improved combination vegetation trimmer and edging unit, further providing, in a preferred embodiment, two equally-convenient operating and control positions, a power source positioned to allow consistent operating balance in trimming or edging, an integrated, large diameter, vertically-flanged roller edging guide, and dual-position activation switches located about the shaft of the unit; and, in an alternate embodiment, the above-referenced power source including a battery.
It is, therefore, to the provision of such an improved unit that the present invention is directed.
Briefly described, in a preferred embodiment, the present invention both overcomes the above-mentioned disadvantages, and meets the recognized needs for such a unit, by providing a vegetation trimmer unit with an operating and control position that changes easily from a position convenient for trimming, to one that is convenient for edging.
The unit, accordingly, is provided preferably with two sets of activation switches which, through their symmetrical location about the control handle of the unit, and when used in association with the multi-position front handle and control handle of the unit, allow the operator to easily flip or rotate the unit into a second operating position (from trimming mode to edging mode and vice versa), and, thereby, to maintain the controls in the exact same position with respect to the operator. In this manner, the convenience to, and safety of, the operator is optimized in either position.
In edging mode, a flanged roller edging guide that is preferably integral to the trimmer housing assembly assists the operator in creating a uniformly-trimmed edge, and eliminates the need for complicated appendages or techniques to perform this function. Advantageous to the present invention, the roller edging guide is integral to the trimmer housing assembly is and concentrically located about the motor shaft. Because of this orientation, the roller edging guide can be of sufficient diameter to allow easy rolling on imperfect reference surfaces, while maintaining a consistent distance between the cutting plane and the object being edged, regardless of the angular orientation of the trimmer with respect to the operator or the working plane.
In a preferred embodiment, the power source (e.g., a battery) for the unit is located in a symmetrical, in-line orientation with respect to the shaft of the unit. This orientation serves to ease the rotation of the unit between control positions, and also facilitates a consistent feel during use in either of the two modes (trimming and edging) of operation. This consistency of feel is manifested in the way that the mass of the power source affects the operational maneuverability of the unit. Accordingly, in either position the unit is equally well balanced.
Thus, it is an object of the present invention to provide a new and improved combination vegetation trimmer and edger that has a multi-position front handle which may be easily indexed amongst positions equally convenient to either operating position.
It is another object of the present invention to provide a new and improved combination vegetation trimmer and edger that has motor activation switches equally convenient to either operating position.
It is a further object of the present invention to provide a new and improved combination vegetation trimmer and edger that has an edging roller with a flange that is integral to the trimmer housing, which operates to assist the operator in creating a distinct trimmed edge, and which eliminates the need for complicated apparatus to perform this function.
It is yet a further object of the present invention to provide a new and improved combination vegetation trimmer and edger wherein the roller edging guide is concentrically located about the motor shaft, and whereby the roller edging guide is of sufficient diameter to allow easy rolling on most surfaces, while maintaining a consistent distance between the cutting plane and the object be edged around.
It is still a further object of the present invention to provide a new and improved combination vegetation trimmer and edger with a power source mounted in a location equally balanced in either operating position.
It is yet a further object of the present invention to provide a new and improved combination vegetation trimmer and edger which may easily be used as a conventional trimmer, intended for use in a horizontal position for grass and weed cutting purposes, and then rotated into a vertical plane to function as a lawn edger, all while providing secure and convenient control of the unit in either such position, along with a balanced aspect and safe operation.
Other objects, features, and advantages of the present invention will become apparent to those ordinarily skilled in the art by reference to the accompanying Drawing Figures and to the Detailed Description of the Preferred Embodiment presented herein.